To gain insight into the mechanisms of gene control, I propose to study the genes related to the major Drosophila heat shock protein of both Drosophila and the bacterium E. coli. The response of organims to heat and other stresses is universal and the proteins induced by treatment have been conserved throughout evolution. We have found a family of genes related to the major heat shcok inducible gene of Drosophila. A number of these genes are transcribed at normal growth temperature and not induced by heat shock. Also we have identified a gene in E. coli which is related to the Drosophila hsp 70 gene and whose transcription is enhanced by heat treatment. The approach to study the regulation and function of these genes will be three-fold. First, we will analyze the transcription of these hsp 70 related genes of Drosophila in different tissues and developmental stages. Secondly, a genetic analysis will be carried out on the 87D Drosophila gene and the E. coli gene to gain insight into the function of these genes. Thirdly, monoclonal antibodies specific for the various protein products will be used to determine the location of these proteins in normal and mutant cells, under normal and heat shock conditions, in order to gain insight into the function of these related proteins. Also, transcription and genetic analysis will be carried out on the 87E actin gene to gain insight into the function and interation of the multigene family of actin genes.